Sliding Mode Control for Hybrid Mass Dampers: Experimental analysis on robustness

This manuscript presents an experimental investigation into the effectiveness of Sliding Mode Control (SMC) for vibration mitigation of a structure equipped with a Hybrid Mass Damper (HMD), as compared to conventional linear controllers. The experimental setup involves a cantilever beam exhibiting a first bending mode at 21Hz, subjected to strong parametric uncertainties and external excitation through a shaker. Additionally, an inertial actuator with internal resonance at 21Hz is utilized to apply passive and active control to the vibrating beam. The SMC approach is compared to three more common HMD control methods: alpha-controller, LQG, and passivity-based control. To highlight the robustness and performance advantages of SMC, the nominal system undergoes significant mass and inertia modifications, not accounted for during the tuning of the observer and the controllers. The performances of the various controllers are then compared on four scenarios: two nominal identified systems and two configurations with uncertain parameters. Experimental results underscore the superior capabilities of SMC in mitigating structural vibrations, showcasing not only enhanced stability but also superior performance when confronted with substantial parametric uncertainties, outperforming traditional linear control methods.